Preparation : For two different takes, try the peppermint-stick and the peanut-butter-and-banana versions that follow.

Line an 8- or 9-inch square pan with foil or waxed paper, letting liner extend a few inches above pan on 2 sides.

Stir condensed milk and butter in a medium-size saucepan over low heat until butter melts. Remove from heat, add chocolate chips and stir until melted and smooth. Stir in remaining ingredients. Spread in prepared pan and refrigerate 8 hours, or until firm enough to cut.